package com.wxd.init;

import com.wxd.AppConfig;
import org.springframework.web.WebApplicationInitializer;
import org.springframework.web.context.support.AnnotationConfigWebApplicationContext;
import org.springframework.web.servlet.DispatcherServlet;

import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.ServletRegistration;

public class MyWebApplicationInitializer implements WebApplicationInitializer {
    @Override
    public void onStartup(ServletContext servletContext) throws ServletException {
        // Load Spring web application configuration
        //通过注解的方式初始化Spring的上下文
        AnnotationConfigWebApplicationContext ac = new AnnotationConfigWebApplicationContext();
        //注册spring的配置类（替代传统项目中xml的configuration）
        ac.register(AppConfig.class);
        ac.refresh();

        // Create and register the DispatcherServlet
        // 基于java代码的方式初始化DispatcherServlet
        DispatcherServlet servlet = new DispatcherServlet(ac);

        if (!servletContext.getServletRegistrations().containsKey("dispatcherServlet")) {
            // 注册前端控制器
            ServletRegistration.Dynamic registration = servletContext.addServlet("dispatcherServlet", servlet);
            // 设置容器启动时就实例化
            registration.setLoadOnStartup(1);
            // 设置url-pattern
            registration.addMapping("/*");
        }
    }
}
